Refining Asphalt Mixture Fatigue Cracking Design Criteria Based on Overlay Testing

Improving fatigue characterization is essential for enhancing the durability and sustainability of asphalt mixtures, leading to increased road resilience, reduced maintenance costs, and minimized environmental impact. The Overlay Test (OT), a crucial method for assessing the susceptibility of asphalt mixtures to fatigue cracking, involves subjecting asphalt mixture specimens to repeated direct tension loads. The cracking susceptibility of a mix with OT is assessed based on performance indices, such as Critical Fracture Energy (CFE) and Crack Propagation Rate (CPR). The existing fatigue cracking criteria for developing a balanced mixture do not account for the aging of the mix and are based on testing minimally aged asphalt mixtures. As asphalt materials age, they become more brittle and less flexible, making pavements more susceptible to cracking and reducing their capacity for healing. Although past research has helped to calibrate OT testing factors (i.e., NCHRP 09-57), little attention has been given to refining design criteria at different aging levels. This research aims to establish criteria that consider the oxidation effect for asphalt mixture design using the OT method. The study will involve thorough data analysis to adjust threshold limits for CFE and CPR when evaluating aged asphalt mixture specimens and generate a research output that differentiates from past studies. The findings obtained from the data analysis will be validated through an experimental investigation. Lastly, recommendations will be provided to implement the research findings. The objectives of this study are the following: (1) Determine if OT criteria used for Balanced Mix Design (BMD) needs to be refined to account for aging; (2) Establish a threshold level for OT criteria at a specific aging level, and (3) Draft an implementation plan to adopt refined OT criteria that consider aging for BMD. Accordingly, the research project is divided into four tasks. Task 1 focuses on comprehensively analyzing OT data from previous research endeavors associated with implementing BMD in Texas and formulating accelerated aging protocols. The primary objectives of this analysis are to quantify the variations in CFE and CPR parameters attributed to asphalt mixture constituents, production, and aging impacts and to establish criteria that account for aging. Task 2 involves conducting experimental validation that corroborates the proposed criteria. This laboratory work will help refine asphalt mixture fatigue cracking parameters based on their constituent materials and aging effects. Task 3 will develop recommendations for adjusting CPR and CFE parameters. The recommendations will provide a practical framework for implementing the research findings and focus on enhancing the durability of asphalt pavements. Task 4 encompasses preparing the final deliverables which will summarize the research results, findings, conclusions, recommendations, and implementation plan.

• Record URL:
  • https://www.sptc.org/cy2-utep-02

Language

• English

Project

• Status: Active
• Funding: $126,128.00
• Contract Numbers:

  CY2-UTEP-02

  69A3552348306

• Sponsor Organizations:

  Office of the Assistant Secretary for Research and Technology

  University Transportation Centers Program
  Department of Transportation
  Washington, DC  United States  20590
• Managing Organizations:

  Southern Plains Transportation Center

  University of Oklahoma
  202 W Boyd St, Room 213A
  Norman, OK  United States  73019
• Project Managers:

  Dunn, Denise

• Performing Organizations:

  University of Texas El Paso

  El Paso, TX   
• Principal Investigators:

  Nazarian, Soheil

  Montoya, Miguel

  Mallick, R

• Start Date: 20241001
• Expected Completion Date: 20250930
• Actual Completion Date: 0
• USDOT Program: University Transportation Centers

Subject/Index Terms

• TRT Terms: Aging (Materials); Asphalt mixtures; Fatigue cracking; Mix design; Pavement design; Tension tests; Test procedures
• Geographic Terms: Texas
• Subject Areas: Design; Highways; Materials; Pavements;

Filing Info

• Accession Number: 01941690
• Record Type: Research project
• Source Agency: Southern Plains Transportation Center
• Contract Numbers: CY2-UTEP-02, 69A3552348306
• Files: UTC, RIP
• Created Date: Jan 1 2025 5:09PM